Folded electrode configuration for galvanic cells

• US 5,525,441 A
• Filed: 09/13/1994
• Issued: 06/11/1996
• Est. Priority Date: 09/13/1994
• Status: Expired due to Fees

• Current Assignee: Saft America, Inc. (Totalenergies Se)
• Original Assignee: Power Conversion, Inc.
• Inventors: Rodriguez, Pedro, Reddy, Thomas B.
• Primary Examiner(s): Maples, John S.
• Application Number:
  US08/305,439
• Time in Patent Office: 637 Days
• Field of Search: 429/127, 429/245, 429/233, 429/192, 429/220, 429/224
• US Class Current: 429/127
• CPC Class Codes: H01G 11/12 Stacked hybrid or EDL capacitors
• CPC Class Codes: H01G 11/52 Separators
• CPC Class Codes: H01G 11/56 Solid electrolytes, e.g. gels; Additives therein
• CPC Class Codes: H01G 11/58 Liquid electrolytes
• CPC Class Codes: H01G 11/82 Fixing or assembling a capacitive element in a housing, e.g. mounting electrodes, current collectors or terminals in containers or encapsulations
• CPC Class Codes: H01M 10/0413 Large-sized flat cells or batteries for motive or stationary systems with plate-like electrodes
• CPC Class Codes: H01M 10/0431 Cells with wound or folded electrodes H01M10/045 takes precedence
• CPC Class Codes: H01M 10/045 Cells or batteries with folded plate-like electrodes
• CPC Class Codes: H01M 10/05 Accumulators with non-aqueous electrolyte H01M10/39 takes precedence
• CPC Class Codes: H01M 10/052 Li-accumulators
• CPC Class Codes: H01M 10/0565 Polymeric materials, e.g. gel-type or solid-type
• CPC Class Codes: H01M 10/38 Construction or manufacture
• CPC Class Codes: H01M 2300/0025 Organic electrolyte
• CPC Class Codes: H01M 6/10 with wound or folded electrodes
• CPC Class Codes: H01M 6/16 with organic electrolyte H01M6/18 takes precedence
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02E 60/13 Energy storage using capacitors
• CPC Class Codes: Y02P 70/50 Manufacturing or production processes characterised by the final manufactured product
• CPC Class Codes: Y10T 29/49108 Electric battery cell making

Abstract

A high density cell stack is provided utilizing strips of flexible cathode material and flexible anode materials folded over each other at right angles. A suitable anode material is lithium and a suitable cathode material is manganese dioxide. The disclosed cell stacks are rapidly manufactured to provide high density cells with good mechanical stability and good stability against shorting.

Claims

1. An electrochemical cell stack comprising:

A) a strip of cathode material having sufficient flexibility to permit folding over of the strip onto itself;

B) a strip of anode material having flexibility sufficient to permit the strip to be folded over onto itself and comprising a lithium foil constructed and arranged with a metal current collector extending along the length of said foil; and

C) non-conductive porous separator means positioned between said cathode strip and anode strip to prevent electrical contact between said two strips and being in contact with an electrolyte, said strips being of sufficient length to permit the formation of a plurality of cells when the strips are folded over onto themselves, said anode and cathode cell stack being folded so that the anodes and cathodes are folded at right angles to each other.

2. The cell stack of claim 1 wherein there are at least 3 folds to provide 3 layers of anodes and 4 layers of cathodes.

3. The cell stack of claim 2 wherein said nonconductive flexible separator material is a porous polymeric material.

4. The cell stack of claim 3 wherein said nonconductive flexible separator material is in the form of an envelope.

5. The cell stack of claim 1 wherein said lithium anode is a laminate comprising in order a first lithium foil layer, a copper current collector strip and a second lithium foil layer.

6. The cell stack of claim 5 wherein said cathode comprises manganese dioxide as the active material.

7. The cell stack of claim 1 wherein the electrolyte is a solid polymer.

8. The cell stack of claim 1 wherein the electrolyte is a liquid electrolyte.

9. An electrochemical cell stack comprising:

A) a plurality of individual cathodes connected together through flexible current collector means;

B) a plurality lithiumfoil anodes connected together through flexible means including a metal current collector; and

C) non-conductive flexible members between said plurality of cathodes and said plurality of anodes, said cell stack assembly having said plurality of cathodes and plurality of anodes folded one on top of the other at right angles.